The state opposition is continuing to turn up the heat on Nationals leader Brendon Grylls, pushing for him to reveal his dealings with mining magnate Clive Palmer over the dropping of a $45 million environmental bond.
Opposition state development spokesman Mark McGowan has questioned why the Barnett government let Mr Palmer's company Mineralogy off a $45 million bond for an iron ore project in the Pilbara.
The mining boss has been a long-time supporter and financial backer of the ruling Liberals and Nationals.
Mr McGowan says Mr Grylls, who is minister for regional development, has questions to answer over the lifting of the bond for the $4 billion Balmoral South project.
On Thursday, he told reporters Mr Grylls had six face-to-face meetings with Mr Palmer over a 15-month period to May this year.
"You have to ask who else gets that sort of treatment."
Mr McGowan said Mr Grylls had not complied with the Freedom of Information Act and should release all diary entries and minutes relating to his meetings with Mr Palmer.
"I need to know and the public needs to know: `What is Brendon Grylls hiding?'"
The Labor frontbencher has written to WA's Corruption and Crime Commission (CCC) and parliament's public accounts committee over the issue.
Yesterday Mr Gryll's office said the minister welcomed an investigation and had "nothing to hide".
Today Mr Palmer released a statement accusing Mr McGowan of "conspiring to stop people participating in democracy".
"The way I see it, Labor's spokesman on state development is conspiring to stop people donating money to the Liberal Party.
"I have been giving money to the Liberals and Nationals for more than 40 years, which is my democratic right," Mr Palmer said.
"Mr McGowan wants to gag individuals because he can see first hand what damage is being caused to the Labor Party nationally."
Mr Palmer said he was seeking a meeting with the WA Labor leader Eric Ripper to discuss the bond issue.
He has argued the environmental bond was not applicable to his company because of an iron ore processing act signed by the Geoff Gallop Labor government in 2002.
That act prohibited the imposition of discriminatory tax rates or charges, he said.
Mines Minister Norman Moore has said his department intended to impose a bond on the Mineralogy project once substantial works had started on the site.
